# WHERE stamp > ...
items.where(:stamp < 3.days.ago, :user_id.EQ(3))
items.where(:stamp.LT(3.days.ago), :user_id.EQ(3))
items.where(:stamp => LT(3.days.ago), :user_id => 3)
items.where(:stamp < 3).and(:user_id => 3)

